The lesson here is that whether you have a business partner, or hire a consultant (two very different things), always have a good, solid contract that has been notarized and signed in front of witnesses, and ensure that you retain the services of a good attorney to write up the contract.
In addition, be very careful what documents, account numbers, confidential information, etc etc you expose when deal with a consultant, and never, ever, give a consultant, or anyone else, your signing authority or independent access to bank accounts, etc.